Chlorinated indigo and process of making same.



UNITED STATES- Patented May 24, 1904.

PATENT OFFICE.

PAUL ERWIN, OBERREIT, OF LUDWVIGSHAFEN-ON-THE-RHINE, GERMANY, ASSIGNOR TO BADISOHE ANILIN 'UND SODA FABRIK, OF LUDWIGS- HAFEN-ON-THE-RHINE, GERMANY, A CORPORATION OF BADEN.

CHLORINATED INDIGO AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent N0. 761,007, dated May 24, 1904.

Original application filed February 11, 1902, Serial No. 93,538. Divided and this application filed February 12, 1903 Serial No. 143,127. (No specimens.) 1

No. 93,538, filed February 11, 1902, for indigo coloring-matter containing halogen.

This invention relates tonew indigo coloring-matters containing chlorin and process of I5 producing same. These products will hereinafter be referred to by the generic term chlorinated indigo.

The process employed in this invention consists, essentially, in converting chlorinated 2O phenylglycocll-ortho-carboxylic acid into, for instance, acetylated chlor-indoxyl derivatives, and finally converting these products.

- into the corresponding chlorinated indigo coloring-matters. This can be carried into practical'eifect by treating a chlor-phenylglycocoll-ortho-carboxylic acid (preferably in the form of its sodium salt) with, say, acetic anhydrid, acting on this result (preferably in the dry and purified state) with, say, caustic- 3 soda solution, and then blowing air through the liquid thus obtained.

The chlorinated phenyl-glycocoll-orthocarboxylic acid employed can be obtained by direct chlorination of phenyl-glycocoll-ortho- 3 5 carboxylic acid itself or by chlorinating the nitril of that acid namely, cyan-methyl-anthranilic acid, which is described in United States Letters Patent No. 662,754, dated N ovember 27, 1900and subsequently convert- 7 4 ing the product obtained in this way into chlorinated phenyl glycocoll-ortho-carboxylic acid by suitable saponification.

In the following examples the nature of this invention is further illustrated; but this invention is not limited to the proportions and conditions given therein. The parts are by Weight and the temperature-degrees refer to the centigrade scale.

Example 1P1oduotz'on of Chlorinated Phom Z-gZyooooZZ-ortho-crrbomylie Acid.

A. From phenyl-gZyooooZl-orthowarbowylio ac2 d.Suspend one hundred and ninety-five (195) parts of phenyl-glycocoll-ortho-carboxy lic acid in six hundred (600) parts of glacial acetic acid and add gradually and stirring the meanwhile seventyone (71) parts of chlorin. Allow it to stand for several hours, pour the result into three thousand (3,000) parts of water, filter, and wash with water until the fil' 6? trate no longer contains hydrochloric acid, as shown by testing with silver nitrate. The monochlor-phenyl glycocoll ortho-carboxylic acid so obtained when purified by recrystallization from ethyl alcohol can be obtained 5 in the form of yellow needles melting at be-' tween two hundred and ten (210) and two hundred and fifteen (215 degrees. If one hundred and forty-two (142) parts of chlorin be employed in place of the seventy-one (71) 7 0 hundred (600) parts of glacial acetic acid and add seventy-one (71) parts of chlorin, cooling the meanwhile. At first solution ensues and then the monochlor-cyan-methyl-anthranilic 5 acid begins to separate out. When no further separation takes place, filter off the solid material and wash with water. The acid when purified by recrystallization from ethyl alcohol occurs in yellow needles melting at about 9 two hundred degrees, (200 If in the above example one hundred and forty-two (142) parts of chlorin be employed, dichlorcyan-methyl-anthranilic acid is obtained. When purified, it melts at about two hundred and twenty-three degrees, (223 To convert the so-obtain ed chlor-cyanmethyl-an thranilic acids into the corresponding chlorphenyl-glycocoll-ortho-carboxylicv acids, boil them with an excess of caustic-alkali solutionsay with caustic soda solution containing about fifteen (15) per cent. of caustic soda (NaOH)-until ammonia is no longer given off. Then cool and precipitate the chlor-phenylglycocoll-ortho-carboxylic acid by means of, say, sulfuric acid. The chlorinated phenylglycocoll-ortho-carboxylic acids so obtained can be converted into their, say, sodium salt by suitable treatment with sodium-carbonate solution and subsequently evaporating to dryness on, say, a boiling-water bath.

Emmnple .Q-Productt'on of Chlorinated [otdigo.

Boil one (1) part of the dry and finely-powdered sodium salt of monochlor-phenyl-glycocoll-ortho-carboxylic acid with from three (3) to four (4) parts of acetic anhydrid until evolution of gas ceases. Then distil off the excess of acetic anhydrid in mono. The dry residue may be directly operated upon; but itv is preferable to extract the same with water and to recrystallize this residue from alcohol, and finally from ligroin. Now saponify this product (which is to be regarded as diacetylchlor-indoxyl) by means of an excess of caustic-soda solution, blow air through the resulting liquid, and collect thedichlor-indigo so resulting in any suitable manner. This product resembles ordinary indigo in its external appearance, but is distinguished from ordinary indigo by its containing chlorin and by producing a clearer and more reddish shade of blue when dyed on cotton froma vat such as is adapted for dyeing with ordinary indigo. This coloring-matter is easily soluble in cold glacial acetic acid, yielding a solution which while cold is blue. It is very easily soluble in cold monohydrated sulfuric acid, yielding a solution which while cold is green. It is easily soluble in cold carbon bisulfid.

If dichlor-phenyl-glycocoll-ortho-carboxylic acid be employed in place of the mono-chlorphenyl-glycocoll-ortho-carboxylic acid in the process just described, then a substance is obtained which is to be regarded as tetrachlor indigo. The tetrachlor indigo so obtained diflers from ordinary indigo in external appearance, its color being far more brilliant than that of ordinary indigo, and this tetrachlor indigo is not changed in color by means of even strong nitric acid (HNOa) in the cold, which is so characteristic a reaction for ordinary indigo. It is further distinguished from ordinary indigo by the fact that fiber dyed with it when wetted with caustic-soda solution containing about thirty-five (35) per cent. caustic soda (NaOH) becomes colorless.

I claim 1. Process for the production of chlorinated indigo, which consists in acting upon cyanmethyl anthranilic acid successively with chlorin, caustic alkali, acetic anhydrid, caustic alkali and air.

2. Process for the production of chlorinated indigo, which consists in acting upon chlorinated cyan -methyl-anthranilic acid successively with caustic alkali, acetic anhydrid, caustic alkali and air.

3. Process for the production of chlorinated indigo, which consists in acting upon chlorinated phenyl-glycocoll-ortho-carboxylic acid successively with acetic anhydrid, caustic alkali and air. I

4. Process for the production of chlorinated indigo, which consists in acting upon acetylated chlorinated indoxyl with caustic alkali and air. V

5. Process for the production of tetrachlor indigo, which consists in acting upon acetylated dichlor-indoxyl with caustic alkali and air.

6. As a new article of manufacture indigo coloring-matter which can be made from acetylated monochlor-indoxyl, caustic-soda solution and air; which contains chlorin and dyes cotton from the vat giving blue shades; which is easily soluble in cold glacial acetic acid yielding a solution which, while cold, is blue; which is very easily soluble in cold monohydrated sulfuric acid yielding a solution which, while cold, is green; which is easily soluble in cold carbon bisulfid.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

PAUL ERWIN OBERREIT. Witnesses: I

JOHN L. HEINKE, JACOB ADRIAN. 

